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The above image is from a digital motion picture entitled: "By Rocket Science into a Sperm Whale's Head: A Virtual Dissection." This film was produced in an attempt to depict and better understand the sound production anatomy within the head of a sperm whale. Reconstructing the whale's head required the use of rocket imaging technology and 3-D computer graphics. The entire film (and all clips) are protected by copyright and all rights are reserved. If you click on the above image you may view a short clip from the film (although it may take a few minutes to load). Various educational products have incorporated versions of the film or images from it. These educational products can be purchased at: www.WhaleScience.com

All of the images and animation sequences on this website are protected by copyright. All rights are reserved. Please do not copy any of the images without written permission from me, Ted W. Cranford, or the copyright holder indicated in the text just below each image. If you would like to use any of these images for personal, commercial, or educational purposes, please contact me for terms, conditions, expressed written permission and/or additional information.

The pages on this website contain images that I have either produced, contributed to, or collected in an attempt to understand the structure and function of cetacean cephalic anatomy (whale head structure). The purpose of this website is to promote understanding of structure and function, primarily using examples from the heads of whales but not exclusively. My hope is, by displaying some of these images and providing some ancillary information, that I might sow seeds of understanding cetacean cephalic form and function. Perhaps by seeing these images and reading the accompanying information your understanding of the subject matter will be attained more quickly and completely than it otherwise might have been.

This first webpage (Volume 1) contains images from sperm whales, perhaps the most enigmatic odontocete. These images also supplement the information presented in a formal article entitled: "The Sperm Whale's Nose: Sexual Selection on a Grand Scale?" This paper was published in the October 1999 issue of Marine Mammal Science. If you want more detailed information about the anatomy in the nose of the sperm whale (and some plausible explanations of its function), go to your nearest university library and read this paper or the references therein.

Subsequent webpages (Volumes) appearing on this website will contain images that convey information about other marine mammals, including toothed whales (odontocetes) and baleen whales (mysticetes), and some non-cetacean marine mammals. I will also periodically post photographs of individuals that have some historic significance to the field of marine mammalogy. Most of the images are initially displayed as low-resolution thumbnails (so they will display more quickly) but most will contain links to higher resolution images that you may examine (just click on the image).

1. Neonate Male Sperm Whale

This is a photograph of a recently postmortem neonate male sperm whale on a beach near Santa Cruz, California in the summer of 1997. The baby whale apparently died after being separated from its mother; it stranded alive and died soon thereafter. This is an odd circumstance because large whale carcasses often drift for several days before they wash up on the shoreline in an advanced state of decomposition. Since this whale died after it stranded, the specimen could be salvaged in excellent condition, making it a perfect candidate for scanning and subsequent dissection. This photograph was taken within hours of death and is therefore valuable for documenting the coloration of this neonate specimen.

2. Sperm Whale Head (reconstructed)

This volume visualization (reconstruction) of the neonate sperm whale's head is from the specimen pictured to the left. The reconstruction was created by stacking serial sections gathered using an X-ray computed tomography (CT) scanner. The scanner operates on the same principles as many hospital CT scanners except that this one was large enough to accommodate a sperm whale! The only CT scanner large enough to scan this sperm whale was originally designed and built to find flaws in solid fuel rocket motors. The specimen was scanned, reconstructed, and analyzed for a research paper in an issue of Marine Mammal Science (Volume 15, number 4, Oct. 1999) dedicated to Professor Kenneth S. Norris. The whale's left eye, lower jaw, and anterior blowhole are all visible in this image.

3. Parasagittal Reconstruction through a Sperm Whale Head

This is a sagittal reconstruction from the volume visualization of the neonate sperm whale's head. This section shows the anatomy inside the head of a sperm whale. The most prominent structure is the spermaceti organ, the large yellow structure along the top of the image. A discussion of the function of the spermaceti organ and a map of the structures in this image can be found in the Marine Mammal Science issue mentioned previously (volume 15, no. 4). Another curiosity in the sperm whale's head is a series of "lensatic" structures below the spermaceti organ. Professor Norris suspected that these structures function as a series of "acoustic" lenses. That notion has still to be tested. The "phonic lips" are seen as two ovoid blue structures just to the left of the spermaceti organ. The bones of the skull are shown in white.

4. Transparent Sperm Whale Head

The sperm whale's nose is the largest in the world, even though there are larger animals. This semi-transparent (3-D) volume visualization of the sperm whale's head shows some of the internal structure of its huge nose. One obvious and intriguing question is, "what is the function of this gigantic nose?" You might be tempted to think that having a large nose means that sperm whales have a keen sense of smell. Actually, most whales probably can smell very little or not at all. The part of the brain used for olfaction (smell) in other mammals is absent or greatly reduce in whales. In addition to breathing, it is thought that the sperm whale's nose is used primarily to make sounds. In fact, some scientists think the sounds sperm whale's make might be loud enough to stun prey. The white pointed structure on the lower right portion of the image is the skull. The large mass to the left of the skull is the whale's nose.

5. Sperm Whale Phonic Lips

At the front of the sperm whale's nose and just inside the blowhole there is a valve that looks like a set of lips. In fact, two of the earliest (1897) scientists to dissect a sperm whale's nose thought they looked like the lips on the face of a monkey. These two French scientists coined the term "museau de singe," which can be translated as "monkey's muzzle," to refer to the structures they found in a sperm whale. Some years later, the eminent cetologist Kenneth S. Norris and his colleague, George W. Harvey, proposed that these lips might be used to generate the loud impulsive sounds made by sperm whales. Evidence gathered in recent years supports their suggestion by demonstrating that dolphins make sounds with the same structures (actually a set of structures that probably evolved from the same precursors, i.e. homologoues). Consequently, it seems appropriate to refer to these structures with a label that incorporates this function. The term "phonic lips" serves that purpose. This photograph of the phonic lips in a sperm whale was taken during a dissection of a neonate that stranded in Capitola, California.

6. Sperm Whale Phonic Lips, (parted)

In the late 1960's Professor Kenneth S. Norris and his colleague, George W. Harvey, dissected a sperm whale and wrote a seminal paper about what they thought were the functions of the structures they found. They made a point of describing the details of the region where these two lips come together. In this photograph they are pulling the phonic lips apart to display the "mortised border." This may be the site of sound generation as the upper and lower lips, actuated by air flow, slap together. Professor Norris' hands are the pair on the left in the image. The large mass and tight construction of these lips require a great deal of force to open the lips even in a postmortem specimen.

7. Sperm Whale Phonic Lips (sagittal section)

This black and white photograph of a section through one of the phonic lips of a sperm whale was produced by Norris and Harvey for their 1970 paper. The epithelium to the left of the sample in the image is cornified and becomes thicker where the lips come together. It is interesting that Dr. Eduardo Degoallda of Spain has found a similar thickening in this region of the phonic lips in modern dolphins. There are a series of grooves that apparently direct and carry the flow of air to the lips during sound generation events. These grooves can be seen in the epithelium near the bottom of the image.

8. Sperm Whale Phonic Lips (gross section)

This black and white photograph of a gross section through the phonic lips of a sperm whale was produced by Norris and Harvey. The light band running across part of the image from the left is from the "morticed border" of one lip. Fine grooves that probably help direct air flow across the lips during sound production can be seen crossing the light band (lip) at right angles and then turning to the left. The larger grooves in the lower part of the image are from regions further along the lips (not pictured). I have seen similar sets of grooves or furrows in the same locations (proximal to the phonic lips) in every odontocete specimen I have examined.

9. Deformed Mandible from a Sperm Whale

This photograph was taken at the British Museum of Natural History. They have about half a dozen specimens with jaws that are twisted or otherwise deformed. Each had mild to severe malformation in the distal portion of the lower jaws. It is intriguing that these carnivorous mammals would be able to grow into adulthood with severely deformed mandibles. This suggests that the distal (twisted) section of the lower jaws may not be needed to catch prey. By contrast the deformed specimens had relatively normal posterior portions of the lower jaws (the portion of the jaw that contains Norris' "acoustic window"). One possible interpretation of this observation is that functions such as peripheral sound reception and/or suction feeding require that the posterior portions of the mandibles need to be formed, and function, normally. More details of this and other possible implications for the loud sounds made by toothed whales can be found in a paper by Kenneth S. Norris and his Danish colleague, Bertel Mohl. The paper is entitled, Can Odontocetes Debilitate Prey with Sound? (American Naturalist, 1983, vol.122, pages 85-104).